President Bush (search) tried Tuesday to begin reviving U.S. support for the war in Iraq and reinvigorating his troubled presidency as the U.S. military death toll topped 2,000.

"I know this is a trying time for our military spouses," Bush said at a Joint Armed Forces Officer Wives' luncheon at Bolling Air Force Base. "We've lost some of our nation's finest men and women in the war on terror."

"And the best way to honor the sacrifice of our fallen troops is to complete the mission and lay the foundation of peace by spreading freedom," he said.

A few hours after Bush spoke, the Pentagon announced a fatality that raised The Associated Press count of military fatalities in the Iraq war to 2,000.

The Senate observed a moment of silence in honor of the fallen. "We owe them a deep debt of gratitude for their courage, for their valor, for their strength," Majority Leader Bill Frist (search), R-Tenn., said. Then, one-by-one, Democrats spoke on the Senate floor to memorialize the dead and criticize the president's Iraq policies.

"Our armed forces are serving ably in Iraq under enormously difficult circumstances, and the policy of our government must be worthy of their sacrifice. Unfortunately, it is not, and the American people know it," said Sen. Edward Kennedy (search) of Massachusetts.

Added Sen. Dick Durbin (search) of Illinois: "Words of tribute are in order to honor the sacrifice of these brave men and women and their loved ones. But words are not enough. We owe them leadership and a clear strategy to bring our troops home with their mission truly accomplished."

Outside the White House, anti-war activist Cindy Sheehan (search) — whose 24-year old son, Casey, died in Iraq last year — said she and others plan to "die symbolically" there over the next four days to protest U.S. involvement in Iraq.

MoveOn.org Political Action unveiled a new television ad that asks "How many more?"

In his 45-minute speech on Iraq, the president hailed the announcement in Baghdad that an election 10 days ago resulted in the adoption of a new constitution. There were some allegations of fraud in the Oct. 15 referendum, but election officials said the voting was fair.

The charter is considered a major step, clearing the way for the election of a new, full-term parliament on Dec. 15. Such steps are important in any decision about the future withdrawal of U.S.-led forces.

"Iraqis are making inspiring progress toward building a democracy," Bush said.

Public support for Bush's handling of Iraq is at its lowest point, 37 percent, roughly where it has been since early August, according to AP-Ipsos polling.

Bush's approval rating also is being weighed down by a special prosecutor's inquiry into the leak of a CIA operative's name, the rocky Supreme Court nomination of White House counsel Harriet Miers (search), high gas prices, hurricane reconstruction costs and declining consumer confidence.

The president's schedule this week tracks these topics: An economic speech in Washington on Wednesday, a tour of hurricane damage in Florida on Thursday and a speech on the war on terror Friday in Norfolk, Va.

Bush, who contends that setting a date for troop withdrawal would aid the enemy's cause, said that to fight Islamic radicals, the U.S. must work to prevent terrorist attacks before they occur, keep weapons of mass destruction out of the hands of "outlaw regimes" and deny radical groups the support and sanctuary of such governments.

"State sponsors like Syria and Iran have a long history of collaboration with terrorists and they deserve no patience from the victims of terror," he said. "The United States makes no distinction between those who commit acts of terror and those who support and harbor them. Any government that chooses to be an ally of terror has chosen to be an enemy of civilization and the civilized world must hold those regimes to account."

Bush sought to emphasize Iraq's progress in a second event of the day, appearing in the Oval Office beside Massoud Barzani (search), the president of the autonomous region of Kurdistan in northern Iraq. The two stood to offer reporters and photographers a view of Barzani's traditional Kurdish outfit — a khaki jacket tucked into matching, loosely pleated pants adorned by a knotted sash at his waist and a red-and-white headdress.

"It wasn't all that long ago if he had of worn this outfit and was captured by Saddam Hussein's thugs he would have been killed for wearing it," Bush said. "He feels comfortable wearing it here because we're a free land. He feels comfortable wearing it in his home country because Iraq is free."